The Direct-zol RNA MiniPrep Plus Kits are RNA purification kits that provide a streamlined method for the purification of up to 100 µg (per prep) of high-quality RNA directly from samples in TRI Reagent or similar. Total RNA, including small RNAs (17-200 nt), is effectively isolated from a variety of sample sources (cells, tissues, serum, plasma, blood, biological liquids, etc.). Isolation of RNA by conventional phase separation was shown to selectively enrich for some species of miRNA, leading to bias in downstream analysis. The Direct-zol method assures unbiased recovery of small RNAs including miRNA. The procedure is easy. Simply apply a prepared sample in TRI Reagent directly to the Zymo-Spin Column and then bind, wash, and elute the RNA. No phase separation, precipitation, or post-purification steps are necessary. The eluted RNA is high quality and suitable for subsequent molecular manipulation and analysis (including RT-PCR, transcription profiling, hybridization, sequencing etc.). The entire procedure typically takes only 7 minutes.